Testing cut-out for arc-lamps.



E. 1. GUAY, TESTING CUT-OUT FOR ARC LAMPS.

APPLICATION FILED JULY 20. 1911.

Patented Oct. 12,1915.

I/VZTZYESSES' INK/51327 4712 EMILE J GUAY, {,ZL NQ A His ATTUHNEK UNITED STATES PATENT oFFIcE. I

EMILE J. GUAY, OE SWAMPSCOTT, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

TESTING GUT-OUT FOR ARC-LAMPS.

Specification of Letters Patent.

application filed July 20, 1911. Serial No. 639,513.

To all whom it may concern:

Be it known that I, EMILE J.' GUAY, a citizen of the United States, residing at Swampscott, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Testing Cut-Outs for Arc-Lamps, of which the following is a specification.

"Thisapplication is in part a continuation of my prior application, Serial No. 544,572,

filed February 18, 1910, for testingv cutouts for are lamps.

The invention relates to electric luminous arc lamps arranged in a circuit that is periodically broken and again established at the central station to cause the feeding of the electrodes, and its object is to. provide a closed circuit through, the'lamp for testing purposes when the lamp is out of'service.

In lamps of the luminous arc type, a crust.

of metallic oxid is liable to form on the tips of the electrodes when they cool, after the lamp is extinguished. These crusts are of highresistance, so that the low voltage test ing current does not readily flow through them, and, if this happens, it becomes difiicult for the testing operator at the power station to distinguish between an open line and a high resistance electrode tip! My invention effectually eliminates this trouble by automatically closing a resistance shunt path across the lamp terminals immediately after the line current is switched off the lamp, said shunt affording a path for the testing current. At. the same time, ll provide a second low resistance path across the lamp terminals, and means for making this shunt path of a comparatively low'resistance when a predetermined voltage is impressed across the same. In the embodiment here illustrated, this means comprises a spark gap. so arranged as to short circuit @peratively connected with the lever o of the circuits of a luminous arc lamp embody ng my mvention. The lamp shown comprises two lower elec- Patented Oct. 12, 1915. Continuation in part of application Serial No. 544,572, filed February 18, 19-10. This trodes 1, 2 inclined toward each other with f their upper ends abutting. The mechanism for feeding these two electrodes upward as they burn away is not shown, being now Well known in lamps of this type. In the lamp shown there is a single upper electrode 3. The lifting magnet 4 has its coils in series with the electrodes, its movable core 5 being pivotally attached to a lever 6 which by means of a link 7 actuates the clutch 8 cooperating with the upper electrode, which is vertically movable forthe purpose of drawing" the arc. The clutch vcotiperates with the tripping platform 9 of the lamp, and the arc is practically stationary and of fixed length.

is a switch, preferably comprising a lever 10 which carries an insulated contact 11 cooperating with a stationary contact 12; the

two contacts being located in a shunt across the arc in series with the lifting magnet. A resistance coil 13 is included in this shunt. When the arc is struck the contacts are separated, but, when the line current is.

switched off and the upper electrode drops, the contacts close together and the shunt circuit is completed.

A spark gap, including stationary contacts 14, 15 and a movable contact 18, is connected across the lamp. The movable contact 18 is carried by the armature 17 which coiiperates with a coil'16 included in series with the spark gap. The distance between *the contacts 14 and 15 is made so short that an arc would cross the gap when a predetermined voltage occurs across the terminals of the lamp.

The cycle of operations of this device is as follows: When the current is 05, theelectrodes are together, the armature of the'cutout magnet and that of the lifting magnet are at rest, and the contacts 11, 12 are closed,

thereby putting the resistance and the elec trodes in multiple and in series with the lifting magnet across the lamp terminals; the contacts 15 and 18 are separated a distance equal to or greater than the distance between contacts 14 and 15. When the ourrent is thrown on and there is no insulating conducting layer are is formed between the electrodes.

slag on the eleCtrOdes, the current passes through the lifting magnet which opens the contacts 11; 12 and draws the electrodes apart and establishes the are. But if a nonor crust has formed upon the luminous electrodes, and current is turned on the circuit, the magnet 4: is energized through the shunt circuit which includes the contacts 11 and 12 and resistance 13. The armature 5 is lifted and the parts are so designed that the contacts 11 and 12 are separated prior to the separation of the electrodes,'and the voltage across the two electrodes is ordinarily sufiicient to break down a slight non-conducting layer that may have formed on the electrode tips. The upper electrode is then lifted and in n case the non-conducting layer on the elec- 60. the testing contacts always close the a ance 13, for testing purposes,

ating current is on the line. };-What -I claim as new, and -b y Letters Patent of the 15, the lamp remaining break the crust or non-conducting layer that may have formed upon the electrode tips. The lamp then remains in this condition, that is, with the upper electrodein engagement with the lower electrode and the contact 18 in engagement with the contact short-circuited until the main circuit is, for the purpose of feeding, broken by automatic mechanism at the central station. thus broken, the coil 16 will be denergized and the spark gap opened. Immediately after this, the main circuit is again closed and the cycle of operation will be repeated as above described.

From the foregoing description, it will be 5 seen that the testing contacts 11, 12, in conjunction with the shunt gap contacts 14, 15 and 18, operate to cause the upper electrode to give a hammer blow to the lower electrode'for the purpose of breaking down any insulating layer that may have formed on the electrode tips and then short circuit the lamp, until, at the central station, the line circuit is again opened and made for the purpose of feeding. ,In addition to this, shunt, magnet coil 4 and resistwhen no operwhich includes the desire to secure United States, is '1.'-In 'an arc lamp, a pair of electrodes,

upon one or both of which When the main circuit 1s are, a normally the electrodes,

means for establishing the closed shunt path across means for opening said shunt path by the arc establishing means,a normally high resistance shunt path across the terminals of the lamp, and means for making this shunt of comparatively low resistance when a predetermined voltage is impressed across the same.

2. In an arc lamp, a pair of electrodes, means comprislng a magnet and its armature for striking the are, a shunt path across the are including said magnet, means re-' sponsive to the movement of the armature for opening said shunt path, a normally hlgh resistance shunt path across the terminals of the lamp, and means for making this shunt of comparatively low resistance when a predetermined voltage is impressed across the same. a

3. In an arc lamp, a pair of electrodes between which the arc is maintained and upon one or both of which a non-conductive layermay be formed, means for establish- 1ng the arc, a testing shunt path connected across the arc, means for open circuiting said shunt path by the arc establishing means, a normally high resistance shunt path across the terminals of the lamp, and means for making this shunt path of comparatively low resistance when the arc establishing means is actuated and the arc fails to start, thereby impressing a relativellly high voltage across said second shunt pat 4. In an arc lamp, a pair of electrodes between which the arc is maintained and a non-conducting layer may be formed, means for establishing the are including a magnet and its armature, a shunt path connected across said electrodes in series with the magnet, means responsive to the movement of said armature for open circuiting said shunt path, and a second shunt path of lower resistance connected across the lamp comprising a twobranch air gap, a low resistance magnet in series therewith, and means for closing one air gap branch by the said low magnet.

- 5. In an arc lamp, a pair of cooperating electrodes, means comprising a magnet for separating the electrodes to establish the arc, a shunt path connected across the electrodes resistance comprislng a resistance and a pair of con- 1 tacts one of which is movable in response to the movement of the armature of said magnet and adjusted to open the shunt path of said contacts prior to the separation of the electrodes, a high resistance shunt path connected across the terminals of the lamp, and means for making this shunt path of comparatively low resistance when a predetermined voltage is impressed across the same.

6. In an arc lamp, a pair of electrodes between which the ,arc is maintained and upon one or both of Which a non-conducting layer may be formed, means for establishing the. are including a magnet and its armature, a shunt path connected across said electrodes in series with the magnet, means responsive to the movement of said armature for open-circuiting said shunt path e prior to the establishment of the arc, and a second shunt path of lower resistance connected across the lamp comprising a two branch a1r gap, a low reslstance magnet 1n series therewlth, and means for closlng one air gap branch by the said low resistance 15 magnet.

In Witness whereof, I have hereunto set my hand this seventeenth day of July, 1911.

- EMILE J. GUAY. Witnesses:

JOHN A. MOMANUS, Jr., FRANK G. HATTIE. 

